LETTER DESIGNATION: This can be found as part of the lot number of your heater.

WICK2A and WICK5C (both have pins) fit newer heaters that have wick drop type shut-off
mechanisms. The wick is automaticaly lowered by pushing a button to the left of the knob
(WICK2A) or turning a little knob to the left of the wick knob (WICK5C). All these heaters
have a feature called a "wick life extender."

WICK1, WICK1D, and WICK5 do not have pins. The wick does NOT automatically drop. These
heaters have SLIDE shut off assemblies that smother the flame by covering the wick with a
metal cover. Onmi heaters have a handle on the right side for this purpose. Radiant
heaters have a slide handle on the left.

WICK1B and WICK5B have pins. The shut off mechanisms are the same as described in
section C. These heaters were made before 1979.